Caloric restriction (CR) retard age-associated physiological changes, delays or prevents most age-associated disease and increases life span. The proposed studies will focus on the molecular basic of cardiovascular aging examining whereby CR may intervene in the link between aging and atherosclerosis. Using a non-human primate model, studies will examine the effect of CR on two major factors in atherogenesis which may be affected by aging: the susceptibility of the artery wall, and the atherogenesis of plasma lipoprotein. The overall hypothesis is that CR reduces the binding of low density lipoprotein(LDL) to arterial proteoglycans. To determine the effects of CR on LDL, LDL will be isolated from plasma of CR and control non-human primates which are in an ongoing aging study. LDL composition and structural characteristics will be determines and their binding potential for arterial proteoglycans will be measured in an vitro assay. The effects of CR arterial proteoglycans will be determined following iliac biopsy of the animals, when proteoglycans will be extracted from arterial tissue segments. Proteoglycans will be purified by proteoglycans will be extracted from arterial tissue, segments. Proteoglycans will be purified by column chromatography and individual proteoglycan types will be identified by biochemical and immunological procedures. Interaction with LDL of proteoglycans from CR and control animals will be measured by an in vitro binding asset. These studies will provide important data on vascular biology in aging and the effect of nutritional intervention in arterial wall metabolism.